From 3e22c6c621032212807b9de6a93768bfcf82f500 Mon Sep 17 00:00:00 2001
From: Simon Shirley <simonshirley@flooringsupplies.co.uk>
Date: Fri, 9 Dec 2022 15:54:23 +0000
Subject: [PATCH] Temporarily store the DisplayMember value and re-apply after
 _internalSource.Dispose() call

---
 DropDownControls/GroupedComboBox/GroupedComboBox.cs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/DropDownControls/GroupedComboBox/GroupedComboBox.cs b/DropDownControls/GroupedComboBox/GroupedComboBox.cs
index 16e5138..3767bf1 100644
--- a/DropDownControls/GroupedComboBox/GroupedComboBox.cs
+++ b/DropDownControls/GroupedComboBox/GroupedComboBox.cs
@@ -127,10 +127,16 @@ private enum RedrawWindowFlags : uint {
 			return (_bindingSource != null) ? _bindingSource.DataSource : null;
 		}
 		set {
+			// temporarily store the DisplayMember value as it is lost on _internalSource.Dispose()
+			string _displayMember = DisplayMember;
+
 			if (_internalSource != null) _internalSource.Dispose();
 			_internalSource = null;
 
-			if (value != null) {
+            // restore the lost DisplayMember value
+            DisplayMember = _displayMember;
+
+            if (value != null) {
 				// wrap the object in a binding source and listen for changes
                 _bindingSource = new BindingSource(value, String.Empty);
 				_bindingSource.ListChanged += new ListChangedEventHandler(mBindingSource_ListChanged);